JP2009271518A - Method for manufacturing color filter, the color filter, and display device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for manufacturing a color filter, by which a coating film with a high concentration of a colorant can be formed uniformly, by using an ink for inkjet printing having a low concentration of the colorant, and to provide a color filter and a display device. <P>SOLUTION: The method for manufacturing a color filter for a display is disclosed, the color filter having a plurality of color pixel layers and barrier walls placed between adjoining color pixel layers on a substrate, and the method includes: a forming step of forming the barrier walls on the substrate; and a charging step of charging a pixel region, surrounded by the barrier walls with an ink for inkjet printing by an inkjet printing system, the ink containing at least a colorant, a dispersant and a crosslinking compound. After the region within the barrier walls is charged, the ink is heat treated to reduce the volume which increases the concentration of the colorant. Continuously, the upper face of the barrier walls charged with the ink is irradiated with active energy rays, to make the wettability (liquid affinity) with respect to the ink improved. Thereafter, the ink is cured by heating. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a method for producing a color filter by an ink jet printing method, a color filter, and a display device.

  There are many ink-jet printing inks (hereinafter sometimes referred to as “inks”) used when manufacturing color filters for display used in liquid crystal display devices, organic EL display devices, electronic paper display devices, etc. by the ink-jet printing method. Proposed.

  For example, Patent Document 1 discloses an ink containing at least a binder component, a pigment, and a specific solvent, and Patent Document 2 discloses an ink containing a pigment, a binder component, and a fluorosurfactant. Discloses an ink containing a specific pigment, a binder component and a solvent.

  In the case of producing a display color filter having a high color density by only one printing by the inkjet printing method, it is necessary to increase the concentration of a colorant such as a pigment in the ink. In the inks disclosed in Patent Documents 1 to 3, when the colorant concentration in the ink is increased and a display color filter is manufactured using the ink, the surface of the coating film of each color formed on the substrate to be printed Concavities and convexities occur on the surface. Such a display filter having unevenness on the surface of the coating film has problems such as display unevenness. Therefore, in the inks disclosed in Patent Documents 1 to 3, it is necessary to reduce the concentration of the colorant in the ink.

  When manufacturing a color filter for display such as a liquid crystal display device, an organic EL display device, and an electronic paper display device by using an ink having a low colorant concentration in the ink, a print with a low color density is obtained only by one printing. Only a copy can be obtained, and therefore, it is necessary to print several times repeatedly. If printing is repeated a plurality of times in this manner, troubles such as ink solidifying in the nozzle portion of the inkjet print head and clogging of the nozzle portion may occur.

  Further, when printing is repeated a plurality of times, the ink after printing is dried, and printing and drying are repeated again, which complicates the production process for producing the display color filter. Furthermore, through such a complicated process for producing a color filter for display, there arises a problem that the production stability of the color filter for display and the uniformity of the coating film are lowered.

JP 2006-284752 A JP 2007-003945 A JP 2007-124202 A

  An object of the present invention is to provide a color filter manufacturing method, a color filter, and a display device capable of uniformly forming a coating film having a high colorant concentration using an inkjet printing ink having a low colorant concentration. is there.

The present invention is a method of manufacturing a color filter for display having a plurality of color pixel layers and a partition wall located between adjacent color pixel layers on a substrate,
Forming the partition on the substrate;
A filling step of filling an inkjet printing ink containing at least a colorant, a dispersant, and a crosslinkable compound into a pixel region surrounded by the partition wall by an inkjet printing method;
A pre-heating step of pre-heating the filled ink for inkjet printing under a condition that does not cure, and reducing the volume;
A treatment step for improving the wettability of the upper surface of the partition wall filled with the reduced volume ink with respect to the ink for inkjet printing;
And a curing step of curing the preheated ink for inkjet printing by heating.

  Further, the present invention is characterized in that an active energy ray that does not crosslink the crosslinkable compound is irradiated as a treatment for improving the wettability of the upper surface of the partition wall filled with the reduced volume ink to the ink for inkjet printing.

  In the invention, it is preferable that the active energy ray is an energy ray having a wavelength region of 180 to 400 nm.

Further, the present invention is characterized in that the active energy ray is irradiated in a range of 10 to 1500 mJ / cm ^{2 in} terms of a wavelength of 254 nm.

Further, the present invention is a method for producing a display color filter having a plurality of color pixel layers and a partition wall located between adjacent color pixel layers on a substrate,
Forming the partition on the substrate;
A filling step of filling an inkjet printing ink containing at least a colorant, a dispersant, and a crosslinkable compound and not containing a solvent in a pixel region surrounded by the partition wall by an inkjet printing method;
A pre-heating step of pre-heating the filled ink for inkjet printing under a condition that does not cure, and reducing the volume;
And a curing step of curing the preheated ink for inkjet printing by heating.

  Further, the present invention is characterized in that the crosslinkable compound is a monomer or oligomer containing at least one ethylenically unsaturated double bond in the molecule.

  The present invention is also characterized in that the crosslinkable compound containing at least one ethylenically unsaturated double bond in the molecule is a (meth) acrylate monomer.

In the invention, it is preferable that the colorant is a pigment or a dye.
In the invention, it is preferable that the colorant is a mixture of a pigment and a dye.

  Further, the present invention is characterized in that, in the preheating step, the capacity is reduced by heat treatment for a predetermined time at a temperature not higher than the curing temperature of the crosslinkable compound.

  The present invention is characterized in that in the preheating step, heat treatment is performed at 50 to 120 ° C. for 30 seconds to 30 minutes.

  Moreover, this invention is characterized by heat-processing at 180-250 degreeC for 10 to 60 minutes in the said hardening process.

The present invention is also a color filter manufactured by the above-described method for manufacturing a color filter.
In addition, the present invention is a display device including the color filter described above.

  According to the present invention, there is provided a method for manufacturing a display color filter having a plurality of color pixel layers and a partition located between adjacent color pixel layers on a substrate, and the partition is formed on the substrate in a forming step. Then, in the filling step, ink jet printing ink containing at least a colorant, a dispersant, a crosslinkable compound, and a polymerization initiator is filled in the pixel region surrounded by the partition wall by an ink jet printing method.

  In the preheating step, the ink for inkjet printing filled is reduced in advance by heat treatment under conditions that do not cure, and after improving the ink wettability on the upper surface of the partition wall filled with the reduced volume of ink, In the curing step, the ink for inkjet printing is cured.

  Thereby, since a coating film is reduced in a preheating process, the coating film with a high coloring agent density | concentration can be formed using the ink for inkjet printing with the low density | concentration of a coloring agent. In addition, since the treatment for improving the ink wettability of the upper surface of the partition wall filled with the reduced volume of ink is performed, a color filter having excellent coating film uniformity can be manufactured.

  According to the invention, as the treatment for improving the ink wettability of the upper surface of the partition wall filled with the reduced volume of ink, active energy rays that do not crosslink the crosslinkable compound are irradiated.

  According to the invention, the active energy ray is an energy ray having a wavelength region of 180 to 400 nm.

Moreover, according to this invention, it processes as the irradiation amount of the said active energy ray in the range of 10-1500 mJ / cm < ² > in wavelength 254nm conversion. As described above, the ink wettability on the upper surface of the partition wall can be improved by irradiation with the active energy ray, and a color filter excellent in uniformity with few steps (<0.3 μm) from the partition wall can be manufactured.

  According to the present invention, there is also provided a method for manufacturing a display color filter having a plurality of color pixel layers and a partition located between adjacent color pixel layers on a substrate. In the forming step, the partition is formed on the substrate. When formed, in the filling step, ink jet printing ink containing at least a colorant, a dispersant and a crosslinkable compound and not containing a solvent is filled in the pixel region surrounded by the partition wall by an ink jet printing method. In the preheating step, the filled ink for ink-jet printing is subjected to heat treatment in advance under conditions that do not cure, and then the volume is reduced. Then, in the curing step, the ink for ink-jet printing is cured.

  Thereby, since a coating film is reduced in a preheating process, the coating film with a high coloring agent density | concentration can be formed using the ink for inkjet printing with the low density | concentration of a coloring agent. Moreover, since the ink for inkjet printing does not contain a solvent, a color filter excellent in the uniformity of the coating film can be produced, and it is excellent in safety to the human body without polluting the environment.

According to the invention, the crosslinkable compound is a monomer or oligomer containing at least one ethylenically unsaturated double bond in the molecule.
Thereby, it is further suppressed that unevenness is generated on the surface of the coating film.

According to the invention, the monomer containing at least one ethylenically unsaturated double bond in the molecule is a (meth) acrylate monomer.
Thereby, it is further suppressed that unevenness is generated on the surface of the coating film.

  According to the invention, the colorant is a pigment or a dye. The pigment or dye as the colorant is uniformly dispersed in the ink, and unevenness on the surface of the coating film is suppressed.

  According to the invention, the colorant is a mixture of a pigment and a dye. The mixture of the pigment and the dye as the colorant is uniformly dispersed in the ink, and the occurrence of unevenness on the surface of the coating film is suppressed.

  According to the invention, in the preheating step, the volume is reduced by heat treatment for a predetermined time at a temperature not higher than the curing temperature of the crosslinkable compound.

  Since the volume is reduced by heat treatment at a temperature lower than the curing temperature of the crosslinkable compound, curing is performed while maintaining fluidity with little state change in the wettability improving process and the curing process following the volume reduction.

  As a result, a color filter having a high colorant concentration and excellent uniformity with few irregularities (steps) can be produced.

  Moreover, according to this invention, it is preferable to heat-process at 50-120 degreeC for 30 second-30 minutes in the said preheating process.

  Moreover, according to this invention, it is preferable to heat-process at 180-250 degreeC for 10 to 60 minutes in the said hardening process.

  Further, according to the present invention, since it is manufactured by the above manufacturing method, a color filter having a high colorant concentration and excellent uniformity can be obtained.

  Further, according to the present invention, by providing the above color filter, a display device capable of displaying a uniform image without display unevenness can be obtained.

  The present invention is a method of manufacturing a color filter for display having a plurality of color pixel layers and a partition located between adjacent color pixel layers on a substrate. In the forming step, the partition is formed on the substrate. In the filling step, ink jet printing ink containing at least a colorant, a dispersant, and a crosslinkable compound is filled in the pixel region surrounded by the partition wall by an ink jet printing method.

First, the ink for inkjet printing used in the production method of the present invention will be described.
The crosslinkable compound used in the present invention is not particularly limited, but preferably contains at least one ethylenically unsaturated double bond in the molecule, and the crosslinkable compound is a monomer or an oligomer. It is particularly preferred. Such a crosslinkable compound may be a monomer alone, an oligomer alone, or a mixture of a monomer and an oligomer.

  Further, when the crosslinkable compound containing at least one ethylenically unsaturated double bond in the molecule is a monomer, such a monomer is preferably a (meth) acrylate monomer, and the above ethylenic When the crosslinkable compound containing at least one unsaturated double bond in the molecule is an oligomer, it is preferably an oligomer of a (meth) acrylate monomer.

  As a monomer of such a crosslinkable compound, as a monomer having one ethylenically unsaturated double bond, butanediol monoacrylate, N, N-dimethylaminoethyl acrylate, 2-hydroxyethyl methacrylate, 2-methoxyethyl acrylate N-vinylcaprolactam, N-vinylpyrrolidone, acryloylmorpholine, N-vinylformamide, cyclohexyl acrylate, cyclohexyl methacrylate, dicyclopentanyl methacrylate, glycidyl acrylate, phenoxy methacrylate, tetrahydrofurfuryl acrylate, 2-phenoxyethyl acrylate, 4 -Hydroxybutyl acrylate, isobutyl acrylate, t-butyl acrylate, 2-ethoxyethyl acrylate, 3-methyl Xylbutyl acrylate, benzyl acrylate, ethoxyethoxyethyl acrylate, methylphenoxyethyl acrylate, caprolactone acrylate, 2-ethylhexyl acrylate, tridecyl acrylate, isodecyl acrylate, isooctyl acrylate, isomyristyl acrylate, isostearyl acrylate, 2-ethylhexyl-di Glycol acrylate, 2-hydroxybutyl acrylate, 2-acryloyloxyethyl hexahydrophthalic acid, neopentyl glycol acrylate benzoate, isoamyl acrylate, lauryl acrylate, stearyl acrylate, butoxyethyl acrylate, ethoxy-diethylene glycol acrylate, methoxy-tri Ethylene glycol acrylic Methoxy-polyethylene glycol acrylate, methoxydipropylene glycol acrylate, phenoxyethyl acrylate, phenoxy-polyethylene glycol acrylate, nonylphenol ethylene oxide adduct acrylate, tetrahydrofurfuryl acrylate, isobornyl acrylate, 2-hydroxyethyl acrylate, 2-hydroxy Examples include propyl acrylate, 2-hydroxy-3-phenoxypropyl acrylate, 2-acryloyloxyethyl-succinic acid, 2-acryloyloxyethyl-phthalic acid, 2-acryloyloxyethyl-2-hydroxyethyl-phthalic acid, etc. Is done.

  In addition, as monomers having two ethylenically unsaturated double bonds, 1,6-hexanediol di (meth) acrylate, 1,8-octanediol di (meth) acrylate, 1,9-nonanediol di (meth) Acrylate, 1,10-decanediol di (meth) acrylate, ethylene glycol di (meth) acrylate, tetraethylene glycol di (meth) acrylate, neopentyl glycol di (meth) acrylate, triethylene glycol di (meth) acrylate, tri Examples include propylene glycol di (meth) acrylate, bis (acryloyloxyethyl) ether of bisphenol A, and 3-methylpentanediol di (meth) acrylate.

  In addition, as a monomer having three or more ethylenically unsaturated double bonds, trimethylolpropane tri (meth) acrylate, pentaerythritol tri (meth) acrylate, pentaerythritol tetra (meth) acrylate, dipentaerythritol penta (meth) acrylate And dipentaerythritol hexa (meth) acrylate.

  Moreover, as an oligomer of such a crosslinkable compound, the oligomer of the compound which is said monomer is illustrated.

  These crosslinkable compounds may be used alone or in combination of two or more. In the present invention, in particular, a compound having two ethylenically unsaturated double bonds in the molecule It is particularly preferable to use in combination with a compound having 3 or more ethylenically unsaturated double bonds in the molecule.

  The content of the crosslinkable compound used in the present invention in the ink for inkjet printing is preferably 10% by weight to 80% by weight, more preferably 20% by weight to 70% by weight.

  The crosslinkable compound used in the present invention is preferably reduced in volume in a fluid state after being printed on a substrate to be printed and further cured by heat treatment.

  The preheating method is not particularly limited, but may be heat-treated for 10 minutes or more in a room at 80 ° C. or higher under atmospheric pressure, or 10 hot air at 80 ° C. or higher under atmospheric pressure. The heat treatment may be performed for 10 minutes or more on a hot plate or the like having a temperature of 80 ° C. or more under atmospheric pressure.

  The colorant used in the present invention is not particularly limited, but an organic pigment having a high color density and transmittance is preferably used. Moreover, it is also possible to use a mixture of an organic pigment and a dye as the colorant.

  The organic pigment is not particularly limited, and may be a compound classified as a pigment in the color index (published by The Society of Dyers and Colorists). Preferred examples include C.I. I. Pigment yellow 1, C.I. I. Pigment yellow 3, C.I. I. Pigment yellow 12, C.I. I. Pigment yellow 13, C.I. I. Pigment yellow 138, C.I. I. Pigment yellow 150, C.I. I. Pigment yellow 180, C.I. I. Yellow pigments such as C.I. Pigment Yellow 185; I. Pigment red 1, C.I. I. Pigment 2, C.I. I. Pigment red 3, C.I. I. Pigment red 254, C.I. I. Red pigments such as C.I. Pigment Red 177; I. Pigment blue 15, C.I. I. Pigment blue 15: 3, C.I. I. Pigment blue 15: 4, C.I. I. Blue pigments such as CI Pigment Blue 15: 6; I. Pigment violet 23:19, C.I. I. Other pigments such as Pigment Green 36; black color materials such as carbon black are exemplified.

  If necessary, the organic pigment can be finely divided by rosin treatment, surface treatment using a pigment derivative having an acidic group or basic group introduced, graft treatment to the pigment surface with a polymer compound, sulfuric acid atomization method, etc. Or a cleaning treatment with an organic solvent or water for removing impurities may be performed.

  Although it does not specifically limit as dye, For example, the compound classified into the dye in the color index (The Society of Dyers and Colorists company publication) may be sufficient, and red, blue, green, yellow, orange, purple, brown, black Examples include water-soluble acid dyes, metal-containing dyes, basic dyes, cationic dyes, direct dyes, reactive dyes, water-insoluble disperse dyes, sulfur dyes, vat dyes, etc. A dye that is slightly soluble in water is preferable, or a water-insoluble dye is preferable, and a disperse dye is more preferable.

  These organic pigments and dyes may be used alone or in combination of two or more.

  The content of the organic pigment or dye used in the present invention in the ink for inkjet printing is preferably 1% by weight to 80% by weight, more preferably 10% by weight to 60% by weight, and further preferably 15% by weight. ~ 50% by weight.

  The dispersant used in the present invention is not particularly limited, and examples thereof include surfactants such as cationic dispersants, anionic dispersants, nonionic dispersants, amphoteric dispersants, silicone dispersants, and fluorine dispersants. Can be used.

  Examples of the cationic dispersant include cationic resins having primary, secondary, or tertiary amino groups, and examples of the anionic dispersant include resins having groups such as carboxylate, sulfonate, and phosphate, Examples of the compounds include resins having a carboxylate group, such as polyacrylate and polystyrene-acrylate, and compounds having a sulfonate group include polyoxyalkylenesulfonate, sodium N-methyl-N-oleyltaurine. Salts, dodecylbenzene sulfonates, and the like are included, and compounds having a phosphate group include polyoxyalkylene alkyl ether phosphates. Furthermore, examples of nonionic dispersants include polyoxyethylene type and amide type, and polyoxyethylene type dispersants include polyoxyethylene alkyl ether, polyoxyethylene alkyl aryl ether, and acetylene glycol. And polyoxyethylene glycol ester copolymers and the like, and the amide type dispersant includes polyoxyethylene fatty acid amide and the like, but the dispersant is not particularly limited thereto.

  These dispersants may be used alone or in combination of two or more.

  Moreover, in the ink for inkjet printing used by this invention, content of a dispersing agent becomes like this. Preferably they are 10 weight%-70 weight%, More preferably, they are 20 weight%-60 weight%.

  In the present invention, a polymerization initiator may be included. For example, an active radical generator that is added to cure ink jet ink after printing on a substrate to be printed and generates active radicals by the action of heat can be used.

  When a polymerization initiator is added, it is preferable to select a polymerization initiator that does not hinder volume reduction under preheat treatment conditions.

  Such a polymerization initiator is not particularly limited, and examples thereof include azo compounds, peroxide compounds, acetophenone compounds, benzoin compounds, benzophenone compounds, thioxanthone compounds, triazine compounds, and oxime ester compounds. Can be mentioned.

  As the azo compound, 2,2′-azobis (4-methoxy-2,4-dimethylvaleronitrile), 2,2′-azobis (4-methyl-2,4-dimethylvaleronitrile), dimethyl 2 , 2′-azobis (2-methylpropionate), 2,2′-azobis (2-methylbutyronitrile), 1,1′-azobis (cyclohexane-1-carbonitrile), 2,2′-azobis [N-2 (propenyl) -2-methyl-propionamide], 1-[(cyano-1-methylethyl) azo] formamide, 2,2′-azobis (N-butyl-2-methylpropionamide), 2,2′-azobis (N-cyclohexyl-2-methylpropionamide), a polydimethylsiloxane unit-containing polymer azo polymerization initiator, and polyethylene glycol Such Ruyunitto containing azo polymeric initiator is exemplified.

  Examples of peroxide compounds include peroxyketals, hydroperoxides, dialkyl peroxides, diacyl peroxides, peroxydicarbonates, and peroxyesters. Peroxyesters include t-butyl-peroxylaur. Examples thereof include rate, t-butyl-peroxy-3,5,5-trimethylhexanoate, t-hexyl-peroxy-isopropyl monocarbonate and the like.

  Examples of acetophenone compounds include diethoxyacetophenone, 2-hydroxy-2-methyl-1-phenylpropan-1-one, benzyldimethyl ketal, 2-hydroxy-2-methyl-1- [4- (2-hydroxy Ethoxy) phenyl] propan-1-one, 1-hydroxycyclohexyl phenyl ketone, 2-methyl-2-morpholino-1- (4-methylthiophenyl) propan-1-one, 2-benzyl-2-dimethylamino-1- Examples include (4-morpholinophenyl) butan-1-one and 2-hydroxy-2-methyl-1- [4- (1-methylvinyl) phenyl] propan-1-one oligomers.

  Examples of the benzoin compound include benzoin, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, and benzoin isobutyl ether.

  Examples of the benzophenone compounds include benzophenone, methyl o-benzoylbenzoate, 4-phenylbenzophenone, 4-benzoyl-4′-methyldiphenyl sulfide, 3,3 ′, 4,4′-tetra (tert-butylperoxy). Examples include carbonyl) benzophenone, 2,4,6-trimethylbenzophenone, and the like.

  Examples of the thioxanthone compound include 2-isopropylthioxanthone, 4-isopropylthioxanthone, 2,4-diethylthioxanthone, 2,4-dichlorothioxanthone, and 1-chloro-4-propoxythioxanthone.

  Examples of the triazine compound include 2,4-bis (trichloromethyl) -6- (4-methoxyphenyl) -1,3,5-triazine, 2,4-bis (trichloromethyl) -6- (4- Methoxynaphthyl) -1,3,5-triazine, 2,4-bis (trichloromethyl) -6-piperonyl-1,3,5-triazine, 2,4-bis (trichloromethyl) -6- (4-methoxy Styryl) -1,3,5-triazine, 2,4-bis (trichloromethyl) -6- [2- (5-methylfuran-2-yl) ethenyl] -1,3,5-triazine, 2,4 -Bis (trichloromethyl) -6- [2- (furan-2-yl) ethenyl] -1,3,5-triazine, 2,4-bis (trichloromethyl) -6- [2- (4-diethylamino- 2-methylphenyl Examples include ethenyl] -1,3,5-triazine, 2,4-bis (trichloromethyl) -6- [2- (3,4-dimethoxyphenyl) ethenyl] -1,3,5-triazine, and the like. .

  Examples of the oxime ester compound include 1,2-octanedione, 1- [4- (phenylthiophenyl)]-, 2- (O-benzoyloxime) [manufactured by Ciba Specialty Chemicals, Inc., trade name: Irgacure OXE 01], ethanone, 1- [9-ethyl-6- (2-methylbenzoyl) -9H-carbazol-3-yl]-, 1- (O-acetyloxime) [manufactured by Ciba Specialty Chemicals, Trade name: Irgacure OXE 02] and the like.

  In addition, for example, 2,4,6-trimethylbenzoyldiphenylphosphine oxide, 2,2′-bis (o-chlorophenyl) -4,4 ′, 5,5′-tetraphenyl-1,2′-biimidazole 10-butyl-2-chloroacridone, 2-ethylanthraquinone, benzyl, 9,10-phenanthrenequinone, camphorquinone, methyl phenylglyoxylate, titanocene compounds and the like can also be used as active radical generators.

  These polymerization initiators may be used alone or in combination of two or more.

  Moreover, in the ink for inkjet printing used by this invention, content in the case of adding a polymerization initiator becomes like this. Preferably they are 1 weight%-20 weight%, More preferably, they are 1 weight%-10 weight%.

  The ink for inkjet printing of the present invention may contain a binder resin in addition to the crosslinkable compound, the colorant, the dispersant, and the polymerization initiator as described above. The ink cured after printing on the substrate becomes a stronger cured product.

  The binder resin is polymerized in advance, and examples thereof include a non-polymerizable binder resin that does not have self-polymerizability, or a polymerizable binder resin in which a polymerizable substituent is introduced into the non-polymerizable binder resin. Examples of the non-polymerizable binder resin include (meth) acrylic resins, polyester (meth) acrylic resins, and epoxy (meth) acrylic resins.

  These binder resins may be used alone or in combination of two or more.

  In addition, the content of the binder resin used in the present invention in the ink for inkjet printing is preferably 5% by weight to 50% by weight, and more preferably 10% by weight to 40% by weight.

  The ink for inkjet printing used in the present invention may contain various known additives such as a filler, a polymer compound other than the binder resin, an adhesion promoter, an aggregation inhibitor, an organic acid, and a curing agent, if necessary. An agent can be contained.

  Here, as an adhesion promoter, vinyltrimethoxysilane, vinyltriethoxysilane, vinyltris (2-methoxyethoxy) silane, N- (2-aminoethyl) -3-aminopropylmethyldimethoxysilane, N- (2- Aminoethyl) -3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, 3-glycidoxypropyltrimethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, 2- (3,4-epoxycyclohexyl) Examples include ethyltrimethoxysilane, 3-chloropropylmethyldimethoxysilane, 3-chloropropyltrimethoxysilane, 3-methacryloxypropyltrimethoxysilane, and 3-mercaptopropyltrimethoxysilane. These adhesion promoters may be used alone or in combination of two or more.

  The ink for inkjet printing used in the present invention needs to make a uniform dispersion system by atomizing a colorant in a crosslinkable compound, a dispersant, a binder resin and other additives. The method for obtaining such a colorant atomization and a uniform dispersion system is not particularly limited, and may be a known method such as a dispersion atomization method using a batch type dispersion peptizer or a continuous dispersion peptizer, such as a roll mill. The colorant can be uniformly dispersed by stirring and mixing using a dispersing machine such as a ball mill, a colloid mill, a jet mill, or a bead mill.

  When the colorant contains a water-insoluble organic pigment or dye, it is not particularly limited, but it is preferable to atomize so that the average particle diameter is in the range of 50 nm to 100 nm.

  The polymerization initiator is preferably added to the composition in which the colorant is uniformly dispersed in this way.

  Such a dispersion composition can be made into an ink for ink jet printing suitable for the ink jet method by subsequent filtration.

  The color filter for display manufactured with such an ink for ink jet printing is not particularly limited, but particularly for STN, TFT liquid crystal display color filters, organic EL display color filters, and electronic paper display color filters. Preferably used. The display color filter manufactured according to the present invention is a color filter in which the uniformity of the coating film is prevented from being lowered. Therefore, the display device including the color filter is a display device in which display unevenness is suppressed.

Next, a method for manufacturing a color filter will be described.
(Formation process)
In the forming step, a partition wall is formed on the substrate between adjacent color pixel layers to partition the color pixels.

  The substrate used in the present invention may be a substrate used for a color filter for display, and is not particularly limited. Inorganic glasses such as quartz glass, borosilicate glass, aluminum silicate glass, and soda lime glass coated with silica on the surface. A transparent rigid material such as artificial quartz glass, or a flexible material such as a transparent resin film or sheet or an optical transparent resin plate is preferred, and a transparent quartz glass or a transparent resin film is particularly preferred.

  In the present invention, a black matrix which is a partition wall is formed on the above substrate by a known method. In this case, the black matrix is not particularly limited, but in the case of forming the black matrix alone, as a light shielding agent, carbon black or black pigment, further red pigment, purple pigment, blue pigment, yellow pigment, green pigment, In addition, thermosetting resin materials and photosensitive resin materials containing known coloring materials of dyes are used.

  In addition, the thermosetting resin material and photosensitive resin material used in the present invention are not particularly limited, but phenol resin material, urea resin material, melamine resin material, benzoguanamine resin material, allyl resin material, alkyd resin material, epoxy Examples thereof include thermosetting resin materials such as resin materials, urethane resin materials, silicone resin materials, and epoxy resin materials, and acrylic photosensitive resin materials, but the resin materials are not limited to these.

  A heat treatment and a photosensitive treatment are performed to cure the resin material, and a black matrix having a predetermined opening pattern is formed on the substrate.

(Filling process)
In the filling step, the ink-jet printing ink containing the colorant, the dispersant and the crosslinkable compound as described above is printed and filled in the pixel region surrounded by the partition wall by an ink-jet printing method.

  In the present invention, ink for inkjet printing can be printed by a known inkjet printing head and apparatus or an apparatus manufactured using a known inkjet printing head. The inkjet print head is not particularly limited, but a known head such as a piezo method, a baffle jet method, or an electrostatic method is used, and the piezo method is particularly preferable.

(Preheating process)
In the preheating step, the ink for inkjet printing filled in the filling step is subjected to heat treatment in advance under a condition that does not cure, that is, a temperature equal to or lower than the curing temperature of the crosslinkable compound, to reduce the volume.

  Specifically, the treatment temperature in the preheating step is a temperature not higher than the curing temperature of the crosslinkable compound.

  Moreover, the heat treatment time in such a preheating step is preferably 10 seconds to 30 minutes.

  The heat treatment in the preheating step may be performed under atmospheric pressure or under vacuum, but may be performed under atmospheric pressure, particularly in an atmosphere of a gas containing at least one selected from oxygen, argon, helium, and nitrogen. preferable.

  There is no particular limitation on the method of preheating treatment, but the heat treatment may be performed in a room at a predetermined temperature, hot air at a predetermined temperature may be blown, or heating is performed on a hot plate at a predetermined temperature. It may be processed.

(Wettability improvement process)
In the wettability improvement processing step, the wettability with respect to the ink for inkjet printing on the upper surface of the partition wall is improved. The preprinted ink for inkjet printing is reduced in volume while maintaining fluidity. In this state, by improving the wettability of the upper surface of the partition wall with respect to the ink for inkjet printing, a color pixel layer with less unevenness (step difference) (<0.3 μm) and excellent uniformity can be formed.

  A treatment method for improving the wettability includes irradiation with active energy rays. The wavelength region of the active energy ray to be irradiated is preferably 180 to 400 nm. Further, in this case, the ink for inkjet printing is one in which the crosslinkable compound is not crosslinked and cured by irradiation with active energy rays.

The irradiation amount of the active energy ray is preferably in the range of 10 to 500 mJ / cm ^{2 in} terms of wavelength 254 nm.

(Curing process)
In the curing process, the ink for inkjet printing filled in the filling process is cured.

  The curing method in the curing step is not particularly limited, but it is preferably cured by heat treatment.

  The temperature in the heat treatment in the curing step is higher than the treatment temperature in the preheating step, for example, preferably 180 to 250 ° C, particularly preferably 200 to 250 ° C.

  The heat treatment time in the heat treatment in the curing step is longer than the treatment time in the preheating step, preferably 10 minutes to 1 hour, particularly preferably 20 minutes to 1 hour.

  In the present invention, the heat treatment in the curing step may be performed under atmospheric pressure or in vacuum, but is performed under atmospheric pressure, particularly in an atmosphere of a gas containing at least one selected from oxygen, argon, helium, and nitrogen. Are preferred.

  There is no particular limitation on the method of heat treatment in the curing step, but heat treatment may be performed in a room at a predetermined temperature, hot air at a predetermined temperature may be blown, or a hot plate at a predetermined temperature may be blown. You may heat-process above.

  As described above, pre-heat treatment is performed in advance to reduce the volume of the ink coating film before curing, thereby forming a coating film with a high colorant concentration using ink for inkjet printing with a low concentration of colorant. can do. In addition, since the ink wettability for ink jet printing on the upper surface of the partition wall filled with the reduced volume of ink is processed, a color filter having excellent coating film uniformity can be manufactured. Furthermore, when the ink for inkjet printing does not contain a solvent, the process which improves the wettability with respect to the ink for inkjet printing of the partition upper surface can be omitted, and it is excellent in safety to the human body without polluting the environment.

  In particular, since the preheating treatment is performed at a temperature lower than the curing temperature of the crosslinkable compound, the color filter is cured while maintaining the fluidity with little state change in the curing process, and producing a color filter having a high colorant concentration and excellent uniformity. Can do.

  EXAMPLES Hereinafter, although this invention is demonstrated further in detail using an Example, this invention is not limited to these Examples.

[Example 1]
(Preparation of blue ink for inkjet printing)
600 parts by weight of 1,10-decanediol diacrylate mixed with 100 ppm of 4-methoxyphenol as a polymerization inhibitor and 400 parts by weight of trimethylolpropane triacrylate mixed with 100 ppm of 4-methoxyphenol as a polymerization inhibitor As a result, a monomer mixture was obtained. This monomer mixture was then 18.6% by weight, ethylene glycol dimethacrylate 72.0% by weight, C.I. I. Pigment Blue 15: 6 is mixed with 7.2% by weight, and a dispersant (manufactured by Big Chemie Japan, trade name: Disperbyk 168) at a ratio of 2.2% by weight, and a pigment dispersion is prepared using a known bead mill. Obtained. When the average particle diameter of the pigment in the obtained pigment dispersion was measured with a microtrack particle size distribution measuring apparatus [manufactured by Nikkiso Co., Ltd., model number: HRA (X-100)], the particle size was in the range of 50 to 100 nm. Yes, it was confirmed that it was able to be distributed without problems.

  Next, the obtained pigment dispersion was filtered through a membrane filter having a pore size of 3 μm to prepare a blue ink for inkjet printing.

(Formation of black matrix substrate)
A negative resin black matrix material (trade name “TK”) manufactured by Sumitomo Chemical Co., Ltd. on a transparent glass substrate for liquid crystal (trade name “Eagle 2000”) manufactured by Corning with external dimensions of 370 mm × 470 mm and a thickness of 0.5 mm. -41 ") was spin-coated, pre-baked at 90 ° C for 110 seconds, and then subjected to patterning exposure through a pattern mask at an exposure amount of 100 mJ / cm ² .

  Then, it developed at the temperature of 24 degreeC using the developing solution which consists of 0.5 weight% potassium hydroxide (KOH) aqueous solution, and formed the black matrix board | substrate. Furthermore, by performing post-baking at 230 ° C. for 20 minutes, a black matrix substrate having a light-shielding portion with a film thickness of 2 μm was obtained.

(Printing with blue ink for inkjet printing)
The blue ink for ink-jet printing prepared as described above was supplied to a known piezo-type ink-jet print head kept at 40 ° C., and from this ink-jet print head, a predetermined opening of the black matrix substrate was printed and filled.

  After filling with blue ink for inkjet printing, heat at 80 ° C. for 30 seconds to reduce the volume of ink filled into the partition opening until it becomes equivalent to the sum of the volume of the opening and the volume that the ink cures and shrinks I let you.

After the volume of the ink was reduced, low-pressure mercury lamp light was irradiated through a 300 nm or less transmission filter, and active energy rays with an irradiation amount (based on 254 nm) of 500 mJ / cm ² were irradiated on the ink surface. In the evaluation performed separately, the contact angle of the ink with respect to the upper surface of the partition wall is reduced from 25 degrees to 5 degrees or less by performing this process. Thereafter, the ink was further heated at a temperature of 230 ° C. for 20 minutes to cure the ink, thereby forming a color filter pattern.

[Examples 2 and 3]
In Example 1, the type and amount of pigment, the amount of dispersant, the amount of monomer mixture (I) containing 1,10-decanediol diacrylate and trimethylolpropane triacrylate, the amount of ethylene glycol dimethacrylate, Changes were made as shown in Table 1 to obtain respective pigment dispersions. Using the obtained pigment dispersion, green ink for ink-jet printing (Example 2) and red ink for ink-jet printing (Example 3) are prepared, and the same method as in Example 1 is used to mark predetermined openings on the black matrix substrate. Copy and harden.

  As shown in Table 5, the obtained colored pattern was a pattern having good uniformity with a small step (partition step) between the coating film and the partition. Further, this operation was repeated to obtain a colored pattern, but the ink jet print head was not clogged, and the production stability was good.

[Examples 4 to 6]
In Examples 1, 2, and 3, 50% of ethylene glycol dimethacrylate was changed to dipropylene glycol methyl ether acetate (DPMA) to prepare blue, green and red pigment dispersions. When the particle diameter of the pigment in the obtained pigment dispersion was measured with the same microtrack particle size distribution measuring apparatus as in Example 1, it was in the range of 50 to 100 nm.

  Next, the obtained pigment dispersion was filtered through a membrane filter having a pore size of 3 μm to prepare blue (Example 4), green (Example 5), and red (Example 6) inks for inkjet printing (Table 2). reference).

  The same operation as in Examples 1 to 3 was performed, and ink for inkjet printing was printed and filled in predetermined openings of the black matrix substrate. Furthermore, after filling with ink, it heated for 30 second at the temperature of 80 degreeC, and the coating film volume was reduced to the volume equivalent to the volume which the opening part volume filled with the ink and the volume by which an ink hardens and shrinks. After reducing the volume of the ink, the same operation as in Examples 1 to 3 was performed to irradiate the active energy rays to improve the wettability of the partition walls with respect to the ink. Then, the color filter pattern was created by further heat curing at a temperature of 230 ° C. for 20 minutes.

  The obtained color filter pattern was a uniform pattern with small steps between the coating film and the partition walls as shown in Table 5.

[Examples 7 to 9]
The same operation as in Examples 1, 2, and 3 was performed to obtain a pigment dispersion. When the average particle diameter of the pigment in the obtained pigment dispersion was measured with a microtrack particle size distribution measuring apparatus [manufactured by Nikkiso Co., Ltd., model number: HRA (X-100)], the particle size was in the range of 50 to 100 nm. there were.

  Next, while stirring the obtained pigment dispersion, 1,2-octanedione, 1- [4- (phenylthiophenyl)]-, 2- (O-benzoyl) as a photopolymerization initiator per 100 parts by weight of the pigment dispersion. Oxime (Ciba Specialty Chemicals, trade name "Irgacure OXE 01") 0.9 parts by weight (Example 7), 0.3 parts by weight (Example 8), 0.2 parts by weight (Examples) 9) and filtered through a membrane filter having a pore size of 3 μm to prepare blue (Example 7), green (Example 8), and red (Example 9) inks for inkjet printing (see Table 3). ).

  The same operation as in Examples 1 to 3 was performed, and ink jet printing ink was printed and filled in predetermined openings of the black matrix substrate. After the ink was further filled, the film was heated at a temperature of 120 ° C. for 5 minutes to reduce the volume of the coating film until the volume of the filled ink became approximately 1/3. After the ink volume was reduced, the color filter pattern was formed by further heat-curing at 230 ° C. for 20 minutes.

  As shown in Table 5, the obtained colored pattern was a pattern having good uniformity with a small step between the coating film and the partition wall (partition wall step). Further, this operation was repeated to obtain a colored pattern, but the ink jet print head was not clogged, and the production stability was good.

[Comparative Examples 1-3]
In Comparative Examples 1 to 3, the preheating step was not performed, and after filling the inkjet printing blue ink, green ink, and red ink of Examples 7 to 9, ultraviolet light having a wavelength of 220 to 400 nm was applied to 500 mJ / After irradiation with cm ² (I-line conversion), the mixture was further heated at 230 ° C. for 20 minutes to cure the blue ink for inkjet printing to form a blue pattern, a green pattern, and a red pattern.

  As shown in Table 5, the color filter produced in this way had a large partition wall difference, and noticeable unevenness was also observed in appearance.

[Comparative Examples 4 to 6]
In Examples 1 to 3, dipropylene glycol methyl ether acetate (DPMA) was mixed as an organic solvent instead of ethylene glycol dimethacrylate, and the pigment was dispersed using a bead mill to prepare a pigment dispersion. When the particle diameter of the pigment in the obtained pigment dispersion was measured with the same microtrack particle size distribution measuring apparatus as in Example 1, it was in the range of 50 to 100 nm.

  After adding a polymerization initiator as in Examples 7 to 9, it was filtered through a membrane filter having a pore size of 3 μm, and ink for blue (comparative example 4), green (comparative example 5), and red (comparative example 6) for inkjet printing Was prepared (see Table 4).

  The ink for ink jet printing prepared as described above was supplied to the ink jet head at room temperature, and from this ink jet head, a predetermined opening of the black matrix substrate was printed and filled in the same manner as in Examples 1-3. After the ink was further filled, the film was heated at a temperature of 120 ° C. for 5 minutes to reduce the volume of the coating film until the volume of the filled ink became approximately 1/3. After the ink volume was reduced, the color filter pattern was formed by further heat-curing at 230 ° C. for 20 minutes.

  As shown in Table 5, the color filter pattern thus obtained had a large partition wall step, and a noticeable unevenness was also observed in its appearance.

(Evaluation method and evaluation results)
With respect to the color filter pattern produced as described above, the partition wall step was measured, and the appearance (color unevenness) was evaluated visually.

  For the barrier rib step, the difference between the lowest part of the coating film surface formed in the pixel region and the upper surface of the barrier rib was measured. Table 5 shows the measured values of the barrier rib steps and the evaluation results of the appearance.

Claims (14)

On a substrate, a method for producing a display color filter having a plurality of color pixel layers and a partition wall located between adjacent color pixel layers,
Forming the partition on the substrate;
A filling step of filling an inkjet printing ink containing at least a colorant, a dispersant, and a crosslinkable compound into a pixel region surrounded by the partition wall by an inkjet printing method;
A pre-heating step of pre-heating the filled ink for inkjet printing under a condition that does not cure, and reducing the volume;
A treatment step for improving the wettability of the upper surface of the partition wall filled with the reduced volume ink with respect to the ink for inkjet printing;
A method for producing a color filter, comprising: a curing step of curing a preheated ink for inkjet printing by heating.   2. The color filter according to claim 1, wherein an active energy ray that does not crosslink the crosslinkable compound is irradiated as a treatment for improving the wettability of the upper surface of the partition wall filled with the reduced volume ink to the ink for inkjet printing. Manufacturing method.   The method for producing a color filter according to claim 2, wherein the active energy ray is an energy ray in a wavelength region of 180 to 400 nm. The method for producing a color filter according to claim 3, wherein the active energy ray is irradiated in a range of 10 to 1500 mJ / cm ^{2 in} terms of a wavelength of 254 nm. On a substrate, a method for producing a display color filter having a plurality of color pixel layers and a partition wall located between adjacent color pixel layers,
Forming the partition on the substrate;
A filling step of filling an inkjet printing ink containing at least a colorant, a dispersant, and a crosslinkable compound and not containing a solvent in a pixel region surrounded by the partition wall by an inkjet printing method;
A pre-heating step of pre-heating the filled ink for inkjet printing under a condition that does not cure, and reducing the volume;
A method for producing a color filter, comprising: a curing step of curing a preheated ink for inkjet printing by heating.   The method for producing a color filter according to any one of claims 1 to 5, wherein the crosslinkable compound is a monomer or oligomer containing at least one ethylenically unsaturated double bond in the molecule. .   The method for producing a color filter according to claim 6, wherein the crosslinkable compound containing at least one ethylenically unsaturated double bond in the molecule is a (meth) acrylate monomer.   The method for producing a color filter according to claim 1, wherein the colorant is a pigment or a dye.   The method for producing a color filter according to claim 1, wherein the colorant is a mixture of a pigment and a dye.   The method for producing a color filter according to claim 1, wherein in the preheating step, the capacity is reduced by heat treatment at a temperature equal to or lower than a curing temperature of the crosslinkable compound.   The method for producing a color filter according to claim 1, wherein in the preheating step, heat treatment is performed at 50 to 120 ° C. for 30 seconds to 30 minutes.   In the said hardening process, it heat-processes at 180-250 degreeC for 10 to 60 minutes, The manufacturing method of the color filter as described in any one of Claims 1-11 characterized by the above-mentioned.   A color filter manufactured by the method for manufacturing a color filter according to claim 1.   A display device comprising the color filter according to claim 13.